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How many people did it take to build the Great Pyramid?

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Re: How many people did it take to build the Great Pyramid?

#81

Post by ReptileMan »

mehrdadn wrote: post #6
obastani wrote: post #5

Earlier quoted context omitted.

Not an answer to your question, but the Sagrada Famila [1] began construction in 1882, and is projected to be completed around 2030. It's an immense (and beautiful) structure. Just want to point out that it's not just a matter of the buildings being built a long time ago; this kind of long-term construction is still happening today.

I... just can't wrap my head around this. Is it that they actually take that long with enough people, or they have too few people working on them?

The fact that Gaudi's original plans were lost in a fire don't help

Re: How many people did it take to build the Great Pyramid?

#82

Post by habosa »

That was definitely interesting but doesn't feel fully thought out. That's how much energy it takes to move the blocks vertically into their position, ok. What about horizontal movements to bring the blocks from the quarry to a staging area to their final place?

Also there doesn't seem to be any consideration of logistics time. Were the 900 men always perfectly positioned to apply their energy to the project? Did they not spend time and energy moving around the building site? Did they ever make a mistake and have to redo a section?

This is a good starting estimate. As anyone who's ever worked on any project knows, the estimate is going to be way too optimistic.

Also: I've been to Giza. It's hot and dry as all hell. Humans are going to be far from perfect labor machines in that climate.

Re: How many people did it take to build the Great Pyramid?

#83

Post by pbhjpbhj »

Fjolsvith wrote: post #14
quxbar wrote: post #7

This is great! Begs the next question - how efficiently did the Egyptian government organize labor?

They hadn't invented unions at that time.

Was Moses the first recorded union rep? A plague of frogs is one up on work-to-rule.

Re: How many people did it take to build the Great Pyramid?

#84

Post by ReptileMan »

idoubtit wrote: post #68
ncmncm wrote: post #60

If they built the Great Pyramid in the advertised 20 years, that means placing a 2.5-ton block every 4th minute, 24 hours a day, 365 days a year. If they stopped at sundown, it's every 2 minutes. If they broke half the year to farm, that's one each minute. But let's guess they had enough surplus to work year-round; so, 2 minutes. Suppose they took 600 years, instead; then it's one per hour. Which is harder to imagine…

Parallelization is not a concept that appears around 2010 when low-end computers gained multiple cores. Most of the blocks were at the bottom levels, where it was easy to put them in place. Teams moving hundreds of blocks simultaneously wouldn't be surprising. This addresses the first point, and I don't want to react to what follows, especially the theory that all archaeologists are in a conspiracy to hide the truth.

The hardest part for me is the engineering of the building. The quarywork and positioning is a matter of having enough labor, carrots and sticks.

But to imagine, make plans, adhere to them is hard.

Re: How many people did it take to build the Great Pyramid?

#85

Post by Balero »

habosa wrote: post #82

That was definitely interesting but doesn't feel fully thought out. That's how much energy it takes to move the blocks vertically into their position, ok. What about horizontal movements to bring the blocks from the quarry to a staging area to their final place? Also there doesn't seem to be any consideration of logistics time. Were the 900 men always perfectly positioned to apply their energy to the project? Did the…

"Also: I've been to Giza. It's hot and dry as all hell. Humans are going to be far from perfect labor machines in that climate"

The climate 4500 years ago was very different in this area, and the world in general. For Egypt and the middle east it was generally a little cooler, but much wetter.

When we are looking back into history, even only a couple of hundred years it is important to remember that the climate, and geography was different. Climate shifts, rivers and coastlines move etc.

Re: How many people did it take to build the Great Pyramid?

#86

Post by watwut »

mehrdadn wrote: post #3
burlesona wrote: post #2

This is very cool to see. The main takeaways for me were: 1. It's easy to underestimate what is possible when you limit thinking to a short timescale. I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. Or conversely, it's easy to overestimate the difficulty of someth…

> I think of the cathedrals, temples, mosques, etc. that have been built all over the world, where the people who started the work knew they wouldn't live to see it finished, but that didn't dissuade them. That's mind-boggling. Why would building a cathedral/mosque/temple take longer than a lifetime (or half)?

You run out of money, wars happen, corruption happen, things get finished later.

Re: How many people did it take to build the Great Pyramid?

#87

Post by jiggawatts »

noneeeed wrote: post #53
jiggawatts wrote: post #49

Earlier quoted context omitted.

That's rather... imaginative. Certainly, water played a role: much of the stone was shipped from quarries some distance away. It's also imaginable that they used canals to bring the blocks further inland, closer to the pyramid construction site. However, the near-vertical water tower and lock system would be a challenge to build today, let alone with the technology of the era. The pyramids were built before the wides…

That was really interesting. Itr's weird to think of how many mundane technologies actually had to be invented, and how things would have worked before. The idea of a boat built without nails is kind of crazy.

Bizarrely, for me, seeing Khufu's ship in person was far more memorable than the pyramids themselves. The pyramids are just... piles of rock. Sure, they're big and impressive, but no more. Without using your imagination, you can't see how they were built, what life was like at the time, or what the technology was like.

The ship was incredible, to my eyes at least. My partner wasn't interested, but she never studied engineering! To my eyes it looked almost modern, yet absolutely bizarre to the point of being nearly alien, but only in the details. The joinery. The rope work. Things like that.

I liken it to seeing a jumbo jet fly over for the first time. It's huge and impressive, like the pyramids. But to me, seeing an airport was the real wonder. All those planes with the engine nacelle covers open, showing the intricate tubing and turbine housings. The bizarre low trucks and specialised equipment that's used nowhere else. The fuel pump trucks that suck up jet fuel from underground pipes. The strange land of endless concrete. People waving glowing sticks. And so on and so forth. It's an entire "world" that's different from the normal world outside. You get to see the inner workings of the technology up close, not just a superficial end product from a distance. That's what it felt like to see Khufu's ship for me. I felt like I had stepped into the era of the Pharaohs.

Re: How many people did it take to build the Great Pyramid?

#88

Post by close04 »

Balero wrote: post #85
habosa wrote: post #82

That was definitely interesting but doesn't feel fully thought out. That's how much energy it takes to move the blocks vertically into their position, ok. What about horizontal movements to bring the blocks from the quarry to a staging area to their final place? Also there doesn't seem to be any consideration of logistics time. Were the 900 men always perfectly positioned to apply their energy to the project? Did the…

"Also: I've been to Giza. It's hot and dry as all hell. Humans are going to be far from perfect labor machines in that climate" The climate 4500 years ago was very different in this area, and the world in general. For Egypt and the middle east it was generally a little cooler, but much wetter. When we are looking back into history, even only a couple of hundred years it is important to remember that the climate, and…

The analysis is only about the effort to lift one cubic meter of stone to an arbitrary height a number of times until you reach the mathematical equivalent of a "pyramid's worth", and then divide this by the average human work capacity. That's it. No other theoretical or practical aspect was considered. No friction, no logistics, nothing else.

The conclusion is that it took 900 men 20 years to lift one 2.6t cubic meter of stone to a specific height again and again. Does anyone considers this to be realistic for any construction project?

Like estimating the Mona Lisa took 5s to paint based on the surface of 0.4 square meters. Or the Sistine Chapel ceiling took a couple of days and a really big brush.

The fact that someone with such a CV [0] came up with this for the IEEE page as anything more than an exercise of imagination is very surprising for me.

[0] https://spectrum.ieee.org/author/vaclav-smil

Re: How many people did it take to build the Great Pyramid?

#89

Post by noneeeed »

jiggawatts wrote: post #87
noneeeed wrote: post #53

Earlier quoted context omitted.

That was really interesting. Itr's weird to think of how many mundane technologies actually had to be invented, and how things would have worked before. The idea of a boat built without nails is kind of crazy.

Bizarrely, for me, seeing Khufu's ship in person was far more memorable than the pyramids themselves. The pyramids are just... piles of rock. Sure, they're big and impressive, but no more. Without using your imagination, you can't see how they were built, what life was like at the time, or what the technology was like. The ship was incredible, to my eyes at least. My partner wasn't interested, but she never studied e…

On a smaller scale, that reminds me of the clock at Wells Cathedral (https://collection.sciencemuseumgroup.org.uk/objects/co1347/...) for 1392. The Cathedral is a great example of its kind, but for me the clock was a lot more interesting. Although that might be bacause I've been to dozens of medieval cathedrals so they do kind of blur into one.

I'd like to visit the Pyramids, but I'm more interested in the insides. Khufu's ship sounds fascinating, will definitely take a look if we go.

Re: How many people did it take to build the Great Pyramid?

#90

Post by mc32 »

habosa wrote: post #82

That was definitely interesting but doesn't feel fully thought out. That's how much energy it takes to move the blocks vertically into their position, ok. What about horizontal movements to bring the blocks from the quarry to a staging area to their final place? Also there doesn't seem to be any consideration of logistics time. Were the 900 men always perfectly positioned to apply their energy to the project? Did the…

Yeah I’d like to see them make comparative calculations for things that were built prior to steam power and where we have detailed records to see if these estimates hold up.
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